Highly filled graphene‐benzoxazine composites as bipolar plates in fuel cell applications

Abstract

This research emphasizes on the development of highly filled graphene-polybenzoxazine composites and investigates thermal, electrical, and mechanical properties of the obtained composites for bipolar plate applications. The composition of graphene loading was achieved to be in the range of 10-60 wt%. The experimental results revealed that at the maximum graphene content of 60 wt% (44.8 vol%) in the polybenzoxazine, storage moduli at room temperature of the composites were considerably enhanced with the amount of the graphene, that is, from 5.9 GPa of the neat polybenzoxazine to about 25

Development of highly conductive graphite‐/graphene‐filled polybenzoxazine composites for bipolar plates in fuel cells

“…T g values of the specimens were 200, 203, 206, 208, and 209 °C having graphene content ranging from 0 to 10 wt %. These findings were higher than the T g value of 174 °C reported for the neat PBA . The maximum T g value was 209 °C at the sample having 10 wt % of graphene which was 35 °C higher than the graphite‐filled PBA matrix.…”

“…The results indicated that graphene acted as catalyst for oxazine ring‐opening polymerization thus accelerated the curing behavior of BA‐a network as observed by Plengudomkit et al . in a previous study . Such finding could be attributed to the appearance of carboxyl group attached on the graphene which was naturally presented during typical graphene synthesis as suggested in the technical data sheet of graphene nanoplatelets‐grade H from XG Sciences .…”

“…Plengudomkit et al . studied bipolar plates based on highly conductive polymer composite using graphene filler . The maximum packing density of 60 wt % graphene in PBA samples was lower than that of graphite‐filled PBA composite samples.…”

Friction and Mechanical Properties of Highly Filled Polybenzoxazine Composites: Nanosilica Particle Size and Surface Treatment

“…The determination of density can provide insight into the nature of the particle dispersion within the polymer matrix as well as the presence of voids or air gap formation in the sample . One of the outstanding characteristics of BA‐a is low A‐stage viscosity and therefore, it provides good filler wetting characteristic and allows large amount of filler or reinforcement to be incorporated in the matrix resin during composite fabrication as previously reported . As expected in nanosilica‐filled poly(BA‐a) composites, the measured densities of the poly(BA‐a) composites filled with hydrophilic nanosilica particles of 7, 14, 20, and 40 nm clearly exhibited a linear relationship with nanosilica contents following the rule of mixture as can be seen in Figure a.…”

“…Highly filled composite systems in polybenzoxazines were initiated in Prof. Ishida's laboratory more than 25 years ago especially for microelectronic packaging applications. Since then, several other highly filled composites based on polybenzoxazines for various interesting applications have been reported such as in high thermally conductive composites, wood substituted polybenzoxazine composites, bipolar plate composites, and friction wear . Typically, the polymer matrix, reinforcement, and the adhesion between the matrix resin and the filler are the key factors controlling properties of composite materials .…”